1. Field of the Invention
This invention relates to a method of filling a liquid into a flow passage inside a function liquid droplet ejection head, in which a liquid is filled into the flow passage inside the function liquid droplet ejection head as represented by an ink jet head. It also relates to an ejection apparatus using a function liquid droplet ejection apparatus which is capable of being filled with the liquid in the above-described method; and to a method of manufacturing a liquid crystal display (LCD) device, a method of manufacturing an organic electroluminescence (EL) device, a method of manufacturing an electron emission device, a method of manufacturing a plasma display panel (PDP) device, a method of manufacturing an electrophoretic display device, and a method of manufacturing a color filter, a method of manufacturing an organic EL; as well as to a method of forming a spacer, a method of forming a metallic wiring, a method of forming a lens, a method of forming a resist, and a method of forming a light diffusion body.
2. Description of Related Art
An ink jet head of an ink jet printer (a liquid droplet ejection head) is capable of ejecting very minute ink droplets (liquid droplets) in the form of dots at a high accuracy. Therefore, it is expected to apply the liquid droplet ejection head to the field of manufacturing various kinds of parts by using, as the liquid to be ejected, function liquids such as special inks, photosensitive resins, or the like.
For example, it is considered to carry out the following operations. Namely, an ejection apparatus equipped with a main carriage which moves relative to the workpiece such as a substrate of a color filter, or the like, is used. A head unit having mounted a plurality of function liquid droplet ejection heads on a subsidiary carriage which is detachably held by a main carriage of the ejection apparatus, is carried into the ejection apparatus. By the movement of the main carriage in this state, the head unit is relatively moved against the workpiece to thereby eject the liquid droplet from each of the ejection nozzles formed in a nozzle forming surface of each of the function liquid droplet ejection heads. The liquid crystal display device, organic EL display device, or the like, is thus manufactured.
This kind of ejection apparatus has the following arrangement. Namely, a liquid is supplied from a common tank to each of the function liquid droplet ejection heads by a slight (or small) head pressure so that the liquid droplet can be ejected at a higher accuracy by the operation of a pump part which is assembled into the liquid droplet ejection head. In a position which is away from the workpiece of the ejection apparatus, there is disposed a cap unit on which a plurality of caps to be connected to a suction pump are mounted so as to correspond to the plurality of function liquid droplet ejection heads of the head unit. When a new head unit has been carried into the ejection apparatus, each of the caps is brought into intimate contact with the nozzle forming surface of each of the function liquid droplet ejection heads in a state in which the head unit has been moved to a position facing the cap unit. The liquid inside the liquid supply tank is filled into the flow passage inside each of the function liquid droplet ejection heads by means of the suction force to be operated upon through each of the caps.
As described above, even if the suction is carried out by the caps, the flow speed of the liquid inside the flow passage inside the function liquid droplet ejection head lowers or drops. As a result, the air bubbles cannot be successfully removed out of the flow passage inside the function liquid droplet ejection head, thereby causing the poor ejection or failure in ejection of the liquid droplet under the influence of the remaining air bubbles. As a consequence, it becomes necessary to repeat the suction operations several times, resulting in the amount of liquid to be consumed at the time of filling, thereby causing a higher running cost.
In view of the above points, this invention provides a method of filling a liquid into a flow passage inside a function liquid droplet ejection head, in which air bubbles can be efficiently removed out of the flow passage inside the function liquid droplet ejection head. It also provides an ejection apparatus which is suitable for carrying out the above-described method, and a method of manufacturing an LCD device, a method of manufacturing an organic EL device, a method of manufacturing an electron emission device, a method of manufacturing a PDP device, a method of manufacturing an electrophoretic display device, a method of manufacturing a color filter, a method of manufacturing an organic EL, as well as a method of forming a spacer, a method of forming a metallic wiring, a method of forming a lens, a method of forming a resist, and a method of forming a light diffusion body.